1. Field of the Inventive Concepts
The inventive concepts disclosed and claimed herein relate generally to a microphone for hearing aids, and more particularly, but not by way of limitation, to a refractive lens coated to generate an electrical analog of an acoustic signal striking an outer surface of the refractive lens.
2. Brief Description of the Prior Art
Hearing aids are electroacoustic devices used to amplify or modify sound for the user. They are typically worn in or behind the ear and include a microphone, an amplifier and a speaker. The microphone receives sound waves and converts the sound to electrical signals. The electrical signals can then be amplified or otherwise processed to amplify certain frequencies while reducing or cancelling others. The amplified/processed electrical signals are then converted back to sound waves which are transmitted to an ear canal and/or the ear drum of the user. Other hearing aid devices transmit the amplified/processed electrical signals to a transducer that converts the signals into mechanical vibrations directly on the tympanic members of the middle ear. Bone anchored hearing aids (BAHA) bypass the outer and middle ear and vibrate the skull and inner ear directly.
Regardless of the final delivery means, all hearing aids require a microphone. Due to problems associated with hearing aid size and weight, and for cosmetic reasons, much effort has been expended to decrease the size of these microphones. However, there is generally a tradeoff between size and performance. For example, to improve directional hearing, constructions often make use of multiple microphones which can become quite noticeable and possibly cumbersome. There is a need for improved microphone designs for hearing aids that are cosmetically desirable and provide improved performance.